This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Corpus callosum morphometry will be assessed in healthy controls and dyslexic children. The corpus callosum region will be delineated manually following a defined tracing protocol. Surfaced based techniques developed at LONI will then be applied to compare groups and to investigate correlations with external factors such as reading ability.